Clinical evaluation of the accuracy of two face scanners with different scanning technologies

Abstract

Objectives

This study compared the clinical accuracy of two different stationary face scanners, employing progressive capture and multi-view simultaneous capture scanning technologies.

Methods

Forty dentate volunteers participated in the study. Soft tissue landmarks were marked with a pen on the participants' faces to measure the distances between them. Clinical measurements were manually obtained using a digital vernier caliper by two independent examiners. The participants were then scanned using one of two stationary face scanners: Obiscanner (Fifthingenium), which employs progressive capture technology requiring the subject's head to rotate during image acquisition, or RAYFace (RAY), which utilizes multiple cameras to simultaneously capture a complete 3D image. The scans were imported into mesh-processing software, and digital measurements were taken by the same examiners. Data analysis included pairwise comparison tests and the calculation of the intra-class correlation coefficient (ICC; α = 0.05).

Results

Digital measurements were significantly longer than clinical measurements across all measured distances (p < 0.001). Comparisons between the scanners revealed that vertical measurements using RAYface exhibited greater percentage differences compared to those using Obiscanner (p < 0.05), while horizontal measurements were more variable with Obiscanner than those obtained using RAYface (p < 0.05). Intra-examiner differences were significant for both methods (p < 0.001), although inter-examiner differences were only significant for clinical measurements (p < 0.001), not for digital measurements (p > 0.05). Inter-examiner reliability for digital measurements was high (ICC≥0.99).

Conclusions

Significant differences were observed in the accuracy of the two stationary face scanners using progressive capture and multi-view simultaneous capture scanning technologies, with each device demonstrating specific strengths and limitations.

Clinical Significance

Although face scanners offer relatively high accuracy and consistency, particularly across different acquisition technologies, careful consideration of their performance characteristics is essential for optimizing accuracy in facial measurements.